My boyfriend is worried about his female betta, Trillian. He has noticed that her gills have been changing in color. They have become very pale and tinged with red. He has also noticed a bulge in her abdomen. She is swimming and eating normally, but he is still concerned. Is her bulge a sign of constipation? What could be causing the discoloration on her gills?

Here's a picture. I'm sorry it's so blurry, but even so, it's easy to make out the redness on her gills.

Here's some info on the tank:
It is a cycled 10 gal with live plants. It is divided in two sections and houses a male betta on the other side and one or two little shrimp per side. They are normally fed hikari pellets, but he has recently tried freeze dried blood worms.
Filter: Aquaclear mini
Ammonia: 0
PH: between 7.6 and 8, he's not totally sure on that
Temp: 80